ICP-AES测定青岛崂山绿茶中的微量元素

采用HNO3-H2O2混合酸,密闭微波消解样品,应用ICP-AES测定青岛崂山绿茶中Al、Ca、Cd、Co、Cr、Cu、Fe、K、Mg、Mn、Na、Ni、Pb、Se、Sr、V和Zn等17种营养元素及重金属元素的含量。测定结果的相对标准偏差均小于3.50%,对17种元素的加标回收率在90.0%—110.2%之间,采用该方法测得的茶叶标准物质（GBW10016）的17种元素的值均在标准值范围内,方法准确度高。实验结果表明青岛崂山绿茶中含有大量对人体有益的元素包括Ca、Co、Cr、Cu、Fe、K、Mg、Mn、Na、Ni、Se、Sr、V和Zn等,另外也检测到含有Al,Cd和Pb等有毒、有害元素,但是含量很低,对人体的不利影响可以忽略不计。

Determination of Trace Elements in Qingdao Laoshan Tea Leaves by ICP-AES

The 17 kinds of elements,including Al,Ca,Cd,Co,Cr,Cu,Fe,K,Mg,Mn,Na,Ni,Pb,Se,Sr,V and Zn in Laoshan tea leaves were determined by ICP-AES with nitric acid-hydrogen peroxide for sealed microwave digestion.The relative standard derivation was below 3.50%,and the recovery of all elements was in the range of 90.0%—110.2% while all elements of the standard tea（GBW 10016） were all in the range of the criterion,and the method was very accurate.The Laoshan Tea contained large amount of useful elements including Ca,Co,Cr,Cu,Fe,K,Mg,Mn,Na,Ni,Se,Sr,V,Zn,etc.In addition,several harmful elements including Al,Cd and Pb were also detected,the content of which were so low that their affection for human body could be ignored.